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In the present work, a mild and simple synthesis of α-amino amides has been developed via the one-pot three-component ABC type Ugi reaction of a wide variety of aromatic aldehydes and primary aromatic amines, and two different aliphatic isocyanides. The reactions took place rapidly at room temperature in the presence of 1-propanephosphonic acid cyclic anhydride (T3P®), rendering possible the highly efficient preparation of an α-amino amide library in medium to excellent yields. This study represents the first case in which T3P® has been used in the Ugi reaction. 相似文献
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Mtys Milen Pter brnyi‐Balogh Andrs Dancs Lszl Drahos Gyrgy Keglevich 《Heteroatom Chemistry》2013,24(2):124-130
New thienopyridine derivatives were synthesized by the reaction of 4‐(methylsulfanyl)‐6,7‐dihydrothieno[3,2‐c]pyridine ( 5 ) with amino acids. The use of β‐amino acids led to thienopyridopyrimidone derivatives ( 9a–g ). Using α‐amino acids, such as glycine and racemic alanine under the same reaction conditions, compounds with two thienopyridine units were obtained. The structure of the novel compounds was confirmed by IR, 13C, and 1H NMR spectroscopy, as well as mass spectrometry, along with single crystal X‐ray analysis. © 2013 Wiley Periodicals, Inc. Heteroatom Chem 24:124–130, 2013; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.21073 相似文献
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Trifonov A Raytchev M Buchvarov I Rist M Barbaric J Wagenknecht HA Fiebig T 《The journal of physical chemistry. B》2005,109(41):19490-19495
Ultrafast structural dynamics concomitant to excitation energy transfer in DNA has been studied using a pair of pyrene-labeled DNA bases. The temporal evolution of the femtosecond pump-probe spectra reveals the existence of two electronic coupling pathways, through-base stack and through-space, which lead to excitation energy transfer and excimer formation even when the labeled DNA bases are separated by one AT base pair. The electronic coupling which mediates through-base stack energy transfer is so strong that a new absorption band arises in the excited-state absorption spectrum within 300 fs. From the analysis of time-dependent spectral shifts due to through-space excimer formation, the local structural dynamics and flexibility of DNA are characterized on the picosecond and nanosecond time scale. 相似文献
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Mtys Milen Pter brnyi‐Balogh Rka Kangyal Andrs Dancs Dvid Frigyes Gyrgy Keglevich 《Heteroatom Chemistry》2014,25(4):245-255
Two series of bis(α‐aminophosphonates) were synthesized by one‐pot three‐component reactions using 4‐phenylenediamine, an aldehyde (2 equiv) and a phosphite (2 equiv), or terephtalaldehyde, an amine (2 equiv), and a phosphite (2 equiv) together with propylphosphonic anhydride (T3P®) in both series as a coupling reagent. The bis(α‐aminophosphonates) were obtained in moderate to excellent yields. The condensations take place under mild conditions and the isolation of the products is simple. 相似文献
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Journal of Optimization Theory and Applications - We consider the classical inverse mapping theorem of Nash and Moser from the angle of some recent development by Ekeland and the authors.... 相似文献
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The synthesis of two novel series of 1,3-disubstituted β-carbolines from 1-aryl-β-carboline-3-carbaldehyde building blocks is reported. In the first case, an efficient synthesis of 1-aryl-β-carboline C-3 tethered tetrahydro-imidazopyridines and their aromatic counterparts was developed. In the second case, the Willgerodt-Kindler three-component reaction was used for the transformation of aldehydes into the corresponding thioamides. 相似文献
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Péter Ábrányi-Balogh András Dancsó Dávid Frigyes Balázs Volk György Keglevich Mátyás Milen 《Tetrahedron》2014
In the present work, a practical synthesis of 1-aryl-β-carboline-3-carbaldehydes as versatile building blocks and their application in Biginelli reaction is reported. The starting material of the four-step synthesis is racemic tryptophan methyl ester. The procedure involves a Pictet–Spengler cyclization, a dehydrogenation, an ester reduction, and an alcohol oxidation step. The β-carboline-3-carbaldehydes were further transformed using a Biginelli reaction into derivatives containing a pharmacologically significant dihydropyrimidine ring at position-3. 相似文献
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Milen G. Bogdanov Pavlina G. Manolova Mariana D. Palamareva 《Tetrahedron letters》2004,45(45):8383-8386
The X-ray analysis of 1-oxo-3-thiophen-2-yl-isochroman-4-carboxylic acid methyl ester 1 confirmed its trans-configuration and a conformation with diaxial H-3 and H-4 atoms in solid state. NMR experiments indicated that trans-1 exists in solution in both expected conformers. In CDCl3 and especially in CD3OD or DMSO, the conformational equilibrium is shifted towards the conformer with diequatorial H-3 and H-4, which was also determined by 2D NOESY experiments. The shift is due to the greater polarity of that conformer deduced by ab initio calculations. 相似文献
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